This motherboard a good starting with this processor, where VCore = 1,1V
In a BIOS a range of exposed values 1,375V-1,95V
But on processor PRESCOTT exhibiting of a voltage is higher 1,6V results... To its falling actually. That is it is real on a socket 0,85V-1,25V volts start to move!

EPoX EP-8NPA SLI Socket 754 NVIDIA nForce4 SLI ATX is undervoltable, though I forgot to check how low. It goes low enough to stay at stock speeds, at least. I only got the Athlon 3000+ (Newcastle?) down to 1.375v (from 1.5v) and the list in the BIOS did go down further than that...

The fan controls didn't seem to work though -- it is still in an early BIOS, and hopefully they will fix this? FWIW, the fan can be shut off below 39C, and then it can have 3 speed steps above that, each with a range of temps and fan speed (percentage of maximum voltage), which shows promise, but in the current BIOS version, it doesn't work, so I had to use a FanMate 2.

Gigabyte GA-K8N Pro SLi (Socket 939) is undervoltable to 0.8v, and the CPU fan header works either "automatically" or manually to control the CPU fan. It can be turned off, and then it can ramp up to three steps, where you can control the temperature, and the speed for each step.

i clicked the link page "Undervoltable Motherboards" and "recommands"
but i got "page not found"
could u modify the link?

DaveSimmons wrote:

Apparently most or all ASUS boards do not allow undervolting p3 and p4 CPUs, they only allow overvolting for overclockers (see the recent Asus P4PE thread).

Since most CPUs are now way overpowered for a home theater PC that's only doing playback, I was thinking of undervolting and underclocking.

Anyone know of p3 or p4 motherboards that undervolt and underclock? Have you done this yourself?

Of course I can always buy some old 815 / BX motherboard and a "slow" p3, but wouldn't an underclocked tualatin celeron 1.2 run cooler than a coppermine p3 or celeron at 800 MHz?

* * * * * * * * * * * *

ADDENDUM by MIKEC: Dave, sorry to hijack your thread, but I think you'll find the intent is perfectly in line with yours... :wink:

A new page called Undervoltable Motherboards has been added to the Recommended Section. This is a short starting list of undervolt-friendly motherboards that will be expanded over time. How quickly this happens depends on how much you help. You can each help a great deal.

The simple fact is that Vcore adjustments are usually not covered in specifications, and often, not even in manuals. In many cases, the only way to know for sure is to go into the BIOS of the motherboard and check the Vcore range available in the CPU frequency/voltage setup menu. Each and every one of you has at least one motherboard, the one in your computer. Most of you have two -- one at home and one at work. Just do a quick check on the BIOS CPU voltage adjustment range of your own PCs and report on any motherboard that provides at least a -0.2V setting from default Vcore setting.

Please submit the information to this thread. I will periodically collect the info and add it to the list below. With everyone's cooperation, we will soon have a large and useful list of undervolt friendly motherboards. If the list gets big enough, we may even divide it up into handy CPU and/or chipset categories.

My socket A Jetway 663AS is not undervoltable SPCR style (only -0.1V is allowed).
I should soon be able to report on the DFI ak75-EC. According to web reviews it allows more than 0.2V undervolting, I will submit it when I can confirm that.

EDIT: OK, it's kind of mixed, the motheboard's BIOS allow to undervolt only down to 1.5V (reported as 1.47V by hardware monitor and speedfan).
So a duron (with stock voltage of 1.5V) can't be undervolted, whereas an Athlon (1.75V) can be undervolted by up to 0.25V. I tested with both processor type, so I can say the voltage array doesn't change with the processor type.
To sum up the way it is done in the article :
discontinued board - DFI AK75-EC - SocketA - VIA KT133A - 1.5V-1.85V - in BIOS

I also notice that the AMI utility is v 2.54, but you mention that your's
is v 2.58.
If it's not possible, maybe you can flash your bios back from 1.1 to v1.0
the only diffence in v1.1 is that they updated the raid option ROM.
If you don't need this, you can go back to v1.0, maybe this will revert
the 2.58 to 2.54?
I'm not sure, but you can try.

Who is online

Users browsing this forum: Google [Bot] and 4 guests

You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot post attachments in this forum